Most of the narrative in I Know Why the Caged Bird Sings takes place in the small, heavily segregated town of Stamps, Arkansas. Stamps is essentially two separate towns, and Marguerite seldom sees a white person unless she has a specific errand in their neighborhood. Marguerite's only experience of a big city is of a stay in St. Louis, Missouri, which proves traumatic when she is sexually assaulted and raped by her mother's boyfriend.
Given this background, it is hardly surprising that San Francisco represents the freedom, anonymity, and sophistication of a big city for Marguerite. It also represents a fresh start. Black and white people mix freely together, and she is able to develop her intellectual gifts at better schools. The city is fast-moving, constantly changing, and full of displaced people. This, paradoxically, makes it feel more like a home to Marguerite, who is happy to lose herself in the crowds.
San Francisco is by no means perfect. Marguerite feels somewhat uncomfortable as one of only three Black girls at her school. However, she does find better and more specialized teaching there than in Stamps. The big city has a variety and latitude that are infinitely refreshing after the stifling atmosphere of a small town. Although no city is safe, the Ku Klux Klan and the virulent racism Marguerite encountered in Stamps are also no longer a threat.